JP2002282619A - Rotary drum filter cloth type solid/liquid separator and method for treatment using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rotary drum filter cloth type solid/liquid separator that can obtain a clear separated liquid at a stabilized treatment capacity with a small driving power and to provide a method for treating sludge or sewage using the separator. SOLUTION: This separator is a rotary drum filter cloth type solid/liquid separator used for concentrating a suspended substance and having a double structure consisting of a rotary drum 1 over which a filter cloth 2 is put up and an outer drum 3, wherein the rotary drum 1 has an inlet 5 for the material to be treated at an upstream of its inside and the drum 3 has an exit 6 for the separated liquid. The filter cloth 2 is suitably a synthetic resin woven cloth having an air permeability of 10,000-1,200 cm<3> /cm<2> .min, and a feed flight 4 may be provided in the inside of the filter cloth. This method is one wherein the above separator is used for the solid/liquid separation of sludge or sewage to obtain concentrated sludge and a clear treated liquid.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solid-liquid separation device, and more particularly to a rotary drum type filter cloth type solid-liquid separation device for separating suspended substances such as sludge from wastewater to obtain a clear separated solution. When,
The present invention relates to a processing method using the same.

[0002]

2. Description of the Related Art Conventional solid-liquid separation techniques include a method using gravity sedimentation, a method using mechanical separation such as a centrifugal separation type, a screen type, a belt type filter cloth type, and a method using membrane separation.
Further, the following sewage treatment methods employ these methods. (1) A method in which activated sludge of biological treatment is subjected to mechanical solid-liquid separation and separated into concentrated sludge and a clear liquid. (2) A method in which sludge having a low concentration is concentrated by gravity sedimentation to increase sludge dewatering treatment efficiency. (3) A method of adding a flocculant and a flocculant to sewage, coagulating, and mechanically separating the coagulated sludge to remove phosphorus, COD, chromaticity, etc. together with the sludge. (4) A method in which the processes (1) and (3) are performed by a membrane separation device.

[0003] Such a conventional technique has the following problems. (1) Regarding the gravity sedimentation method, when gas such as carbon dioxide is mixed in the inflowing sewage, the sedimentation becomes poor,
A clear supernatant cannot be obtained. When a nitrogen component is contained, a denitrification reaction occurs in the settled sludge, and the sludge floats by the buoyancy of the nitrogen gas. (2) The centrifugal concentrator requires large power for high-speed rotation, and the sludge recovery rate is as low as about 90%, so that a clear separated liquid cannot be obtained. (3) Regarding the screen type concentrator, clogging of the screen element is liable to occur, and when the aperture of the element is increased, sludge flows out and a clear separated liquid cannot be obtained.

(4) Regarding the belt type filter cloth type concentrator,
Sludge overflows from the filter cloth side end, and the properties of the separated liquid are likely to deteriorate. Further, replacement of the filter cloth is complicated. (5) In the case of the membrane separation method, the cost of the membrane separation device main body is high, the permeation flow rate is easily reduced due to clogging of the membrane, and stable treatment amount management is complicated. In particular, in a facility that simply treats human waste septic tank sludge and sewage and discharges it to the sewer, the treated water standard value is generally 150 to 600 mg / L of suspended solids. The concentration of suspended solids in the liquid does not reach that level, and equipment for more advanced treatment is required. In addition, since the processing solution (permeate) obtained by membrane separation is processed to a concentration of suspended solids below the detection limit, if the quality of the treated water is not so high, the equipment becomes excessively large and wastes equipment costs. I do.

[0005]

SUMMARY OF THE INVENTION In view of the above-mentioned prior art, the present invention is directed to a rotary drum type for solid-liquid separation of suspended substances, which can obtain a clear separated solution with a small amount of power and a stable processing capacity. An object of the present invention is to provide a filter cloth type solid-liquid separation device and a treatment method capable of effectively using the same to obtain required treatment water quality at low equipment cost.

[0006]

In order to solve the above-mentioned problems, the present invention has a double structure of a rotary drum covered with a filter cloth and an outer body, and an inlet for an object to be processed is provided upstream of the inside of the rotary drum. And a rotary drum-type filter-cloth type solid-liquid separator for concentrating suspended substances having an outlet for the separated liquid in the outer shell. In the rotary drum type filter cloth type solid-liquid separation device,
As a filter cloth, air permeability of 10,000 to 1,200 cm ³
/ Cm ² · min woven cloth made of synthetic resin can be used, and a feed blade may be provided inside the filter cloth of the rotary drum. Further, in the present invention, the rotary drum type filter cloth solid-liquid separator is used for solid-liquid separation of sludge or sewage, and a method for treating sludge or sewage to obtain a concentrated sludge and a clear treatment liquid. is there. In the treatment method, solid-liquid separation of sludge or wastewater can be performed by adding a flocculant and / or a flocculant.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the present invention, a filter cloth is provided on the inner surface of a rotary drum type screen, and sewage is supplied to the inner side. Solid-liquid separation is performed. The sewage to be treated can be added to a flocculant, a flocculant aid, or a combination thereof, depending on the required suspended solid concentration of the treated water, coagulated, and then supplied to the apparatus. FIG. 1 is a sectional view showing an example of a rotary drum type filter cloth type solid-liquid separation device according to the present invention. As shown in FIG. 1, the present apparatus has a double structure of a rotating drum 1 on which a filter cloth 2 is stretched and an outer shell 3.
The feed blades 4 may be provided inside the filter cloth, or the rotation shaft of the rotary drum 1 may be provided with a slight inclination. The sewage is supplied upstream from the liquid supply pipe 5 and moves downstream while being filtered and concentrated by the rotation of the drum. The treatment liquid filtered by the filter cloth is collected by the outer shell and flows out from the filtrate outlet 6. The concentrated liquid overflows from the downstream end of the rotating drum and is discharged from the concentrated sludge outlet 7. The filter cloth stretched on the inner surface of the apparatus is made of synthetic resin such as woven cloth such as twill weave, satin weave or plain weave with air permeability of 10,000 to 1,200 cm ³ / cm ² min.
It can be selected depending on the coagulation method and required treatment water quality.

The number of rotations of the drum can be varied in the range of 4 to 15 rpm according to the degree of concentration. In order to prevent clogging of the filter cloth, high-pressure water can be continuously or intermittently sprayed from a spray nozzle for washing as required. The filter cloth has a cylindrical shape corresponding to the inner diameter of the rotating drum, and can be easily attached / detached / replaced by removing the front cover and the guide of the outer body. This apparatus can be suitably used in the following processing. (1) As precipitation separation and coagulation separation equipment after biological treatment,
The suspended substance is removed to obtain a clear processing solution. (2) Concentrate sludge to increase sludge concentration and increase dewatering efficiency. (3) As an alternative to membrane separation equipment in sewage treatment facilities,
Remove suspended material. (4) As a pretreatment of the sewage treatment, a suspended substance is removed before performing a biological treatment or a physicochemical treatment.

[0009]

The present invention will be described below in more detail with reference to examples. Example 1 This example was performed using a biologically treated activated sludge mixture in a human waste treatment facility. The mixed liquid of the activated sludge of the nitrification tank of the night soil treatment facility was fed to a rotary drum type screen actual machine covered with a filter cloth, and the treatment performance was measured. Table 1 shows the properties of the nitrification tank activated sludge mixture.

[Table 1] 10 mg / L polymer and 400 mg sulfate band in stock solution
/ L was added and aggregated, and then supplied to an actual machine to measure the properties of the filter cloth permeation separated liquid. Table 2 shows the measurement results.

[0010]

[Table 2] When the air permeability of the filter cloth became smaller (= the size of the eyes became smaller), the amount of liquid supplied decreased, but as a whole, the SS was 97%.
With the above-described removal effect, a clear processing solution could be obtained. Further, the SS concentration of the concentrated liquid is 5% or more, and the concentration of sludge is good.

[0011]

According to the present invention, the following effects can be obtained. (1) It is possible to effectively separate solid-liquid from aerated sewage. (2) By selecting the air permeability of the filter cloth to be used, it is possible to obtain a separated liquid having properties suitable for the required treated water quality. (3) Low power because of low rotation speed, and no problem of noise and vibration. (4) Since the size of the mesh of the filter cloth is larger than that of the membrane separation, clogging hardly occurs. (5) The structure is simple and the equipment cost is low.

[Brief description of the drawings]

FIG. 1 is a cross-sectional configuration diagram showing an example of a separation device of the present invention.

[Explanation of symbols]

1: rotating drum, 2: filter cloth, 3: outer shell, 4: feed blade,
5: supply pipe, 6: filtrate outlet, 7: concentrated sludge outlet, 8:
front cover

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification FI theme coat ゛ (Reference) C02F 11/12 (72) Inventor Ryuichi Numata 3-5-1 Inadera, Amagasaki City, Hyogo Prefecture Daiki Kogyo Co., Ltd. F-term (reference) 4D015 BA04 BA05 BA11 BA19 BA29 BB08 BB12 CA02 CA11 DA05 DB01 EA37 EA39 4D026 BA03 BB01 BB08 BC23 BC24 BC26 BC30 BD05 BE01 BE07 BE15 BF09 4D059 AA02 AA23 BE12 BE13 BE19 BE55 BE56 CB01 CB01

Claims (5)

[Claims] 1. A suspension having a double structure of a rotating drum covered with a filter cloth and an outer shell, having an inlet for an object to be processed upstream of the inner side of the rotating drum and an outlet for a separated liquid in the outer shell. A rotary drum type filter cloth type solid-liquid separator for concentrating substances. 2. The filter cloth according to claim 1, wherein the air permeability is 10,000 to 1,
^2. The rotary drum type filter cloth type solid-liquid separation device according to claim 1, wherein the cloth is a synthetic resin woven fabric of 200 cm ³ / cm ² · min. 3. The rotary drum according to claim 1, wherein a feed blade is provided inside the filter cloth.
The rotary drum type filter cloth type solid-liquid separation device according to the above. 4. A rotary drum type filter cloth type solid-liquid separation apparatus according to claim 1, 2 or 3, which is used for solid-liquid separation of sludge or wastewater to obtain concentrated sludge and a clear treatment liquid. Sludge or wastewater treatment method. 5. The method for treating sludge or sewage according to claim 4, wherein the solid-liquid separation of the sludge or sewage is performed by adding a flocculant and / or a flocculant.